It seems to me that the evidence is clear:
Epiphanies can change the world, if our behaviours change in a way that significantly effects the behaviours of others as a result.
If we keep the epiphanies to ourselves, then they have no effect.
To make a change in the world, it is not enough just to think it, we need to act it, to be it, in a way that it spreads to others.
The faster it spreads to others, the more rapid the change.
And one of the things my dad said to me many times was – you have as many ideas as a dog has fleas, and most of them as much use. I always loved the way he used the word “most:” – most is not all. Some of those ideas might actually be useful – and some have proven so – others are yet to prove so.